These presumed Springwater Dancers Argia plana were in the Davis Mountians, Jeff Davis county, Texas on August 06, 2009:

1) This male was at the Chihuahuan Desert Research Institute in Modesto Canyon, below the seep and thus along a stretch of permanent shallow, slow-flowing, vegetation-lined water, with riparian overhanging low canopy. Most of the creek below the seep is on private land and there is less than 100 yards of flowing water before the fence:

Note the elongated black rectangle at the base of the humeral stripe, and the black saddle-shaped bilateral mark on S2 - both thought to be characteristic of Spine-tipped Dancer A. extranea:

S8 and S9 are all-blue (as in Springwater and wrong for Spine-tipped), and the general appearance of the appendages looks much better for Springwater than Spine-tipped:

2) This individual with a strongly-forked humeral stripe was just 4 feet from the insect featured above:

3) The next two were on a private section of Limpa Creek about 15 miles from Modesto Canyon (and a different drainage):

Note the elongated black rectangle at the base of the humeral stripe, and the black S2 marks almost creating the saddle shape: